Circuit Description
The engine control module (ECM) monitors the fuel rail pressure (FRP) via a FRP sensor. When the fuel rail pressure is high the signal voltage is high. When the FRP is low the signal voltage is low. If the FRP is not above the lower limit for the sensor, DTC P0192 will set.
DTC Descriptor
This diagnostic supports the following DTC:
DTC P0192 Fuel Rail Pressure (FRP) Sensor Circuit Low Voltage
Conditions for Running the DTC
| • | DTCs P0642 or P0643 are not set. |
| • | The ignition is ON. |
Conditions for Setting the DTC
The ECM detects the signal circuit is less than 1.2 MPa.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests for the proper operation of the circuit in the low voltage range.
-
This step tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |
2 |
Is the Actual Fuel Rail Pressure parameter within the specified range? | 1.2-1.9 MPa | Go to Intermittent Conditions in Wiring Systems | Go to Step 3 |
Is the Actual Fuel Rail Pressure parameter less than the specified value? | 175 MPa | Go to Step 4 | Go to Step 5 | |
Test the signal circuit of the FRP sensor for a short to ground or high resistance. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 7 | Go to Step 6 | |
5 | Replace the FRP sensor. Refer to Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 7 | -- |
6 | Replace the engine control module (ECM). Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 7 | -- |
7 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 8 |
8 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
